The bypass is in double door cabinet back by the TV. Inside you will see two covers one is to reach the bypass I think its the lower one not sure I haven't taken my 3400RL home from the dealer yet but when we did the walk through he did show me where it was located. Hope this will help you out some.

Hey guys I have used mine this year. On the back side of the bar below the over head cabinet you will see a loovered panel at floor level. Remove the screws and you will see to the right the by pass connection inside the cabinet. You just need to turn the valve to close of the heater, insert the open tube end into your jugs of antifreeze and then open the furtherest faucet away first. Work your way back to the kitchen. Don't forget the outside shower. Just run each faucet until it turns pink and you are good to go. It took about four gallons to do my unit. I do leave the water heater on electric and plugged in to AC so it keeps it warm. Hope this helps.

Native Tex, did you say you leave the water heater turned on? If so this is not good, it should be drained by removing the diode plug. I have replaced my diode once already. By leaving it turned on, eventually it will evaporate all the water and burn up the heating element.
Bill

Wayne and Cathy, to dewinterize you first should run fresh water through the system while the water heater is still bypassed. Run the water until you have clear water out of each faucet. Then turn the bypass valve 90 degrees to "unbypass" the water heater. Let water flow until the water heater is full.

Technically you could unbypass the water heater first but then is will run the pink stuff into the water heater. That won't hurt anything as it's non-toxic. I just prefer not to have any pink left in the water system.

Fill the fresh water tank if you want. Or not. You should then be set to go.